The aim of this investigation is to obtain the neurochemical and neuropharmacological data necessary for understanding the role of mucopolysaccharides (glycosaminoglycans) and glycoproteins in neural processes. There is evidence that these complex carbohydrates are involved in the saltatory conduction of nerve impulses by affecting ion movements at the nodes of Ranvier, and in synpatic transmission at the levels of the synthesis, storage, and release of neurotransmitter amines. The axoplasmic transport of mucopolysaccharides supports the concept that they are utilized in some capacity at nerve endings. If, as now seems very likely, they are also present as cell surface components of neurons and glia and/or as an extracellular ground substance in the central nervous system, they might be expected to play important roles in mediating specific cell-cell interactions, and in regulating the movements of ions and other substances in the extracellular space of brain. We have previously studied the structure, distribution, and metabolism of mucopolysaccharides in adult and developing brain, as well as in purified neuronal, glial, and subcellular fractions. As a continuation of these investigations we are now planning to focus particular attention on mucopolysaccharides and glycoproteins in nervous tissue membranes and their possible involvement in cell-cell interactions, as well as on the role of the soluble chondroitin sulfate proteoglycans of brain. Our work on mucopolysaccharides in relation to the storage and release of biogenic amines will be expanded to include synaptic vesicles of brain and peripheral adrenergic nerves, as well as certain hormone-containing secretory granules of the pituitary. We also plan to examine in more detail the mucopolysaccharides of neuronal cell bodies and brain nuclei, and to determine whether alterations in nervous system function produced by selected psychotropic drugs affect the levels or turnover of mucopolysaccharides in specific subcellular fractions of brain.